Ok so a few weeks a go my 87 4runner with a 22re started having a rough idle. It normally ran around 750-800rpm. It would intermittently drop to 400-500rpm and and be rough. Last week I ran out of gas. (the low fuel light never having turned on) and after fuel was added the truck would not maintain idle. Once I let off the accelerator the idle would drop to 0. As I was driving it however, it ran fine. I got home and started to look around and noticed that the Dash Pot was somewhat old and torn and perhaps was releasing to soon or too far. So I plugged the line once I had the idle where I wanted it. This worked for a while but now we are back to the same situation with the idle dropping to around 400-500rpm. I checked for vacuum leaks with the propane but found nothing really. I will try the carb cleaner today and maybe even the cigar method. Also removed the intake hose from the throttle body and there was nothing clean as a whistle. Last night a new symptom started. As I would rev up the engine and release the pedal I could head a relay click behind the passenger kick panel. Every time I released the pedal quickly I would hear it click. This is new with the release of the pedal but I had heard this relay before when the rpm’s would drop to 400 that relay would go crazy clicking away as the truck struggled to stay running. Could it be the throttle sensing unit that is going out? Or am I just missing a vacuum leak somewhere?
Oh yeah almost forgot to mention that I noticed that I got on the breaks pretty hard a couple of times and the rpm's dropped out and stalled. At that point the engine started with the rpm's completely dropping out. actually when I ran out of gas that is the exact situation that happened traffic had stopped suddenly on the freeway I hit the brakes hard and the truck stalled and would start but not keep running. Being low on fuel I figured I ran out of gas but now in retrospect and having it happen with a full tank of gas I may not have actually run out of gas. It may have simply done then what it is doing now. So vacuum issue related to the brake booster?
